
The best speaker setup – guidelines for best setup
For perfect stereo presentation, speaker setups should observe the following:
1. Setup of an isosceles triangle by speaker and listener, the stereo triangle.
2. Symmetrical acoustic ratio for the first reflection
3. The ratio of sound energy at the ear formed by direct sound should be as large as possible.
4. Select the best rear wall and side wall distance
5. Observe mode formation in the bass range
The objective of setup optimisation for speakers should be a setup where the left and right stereo information
meet at the listener's ears to result in a balanced, natural sound. This requires symmetry. Only for acoustically
symmetrical setups can be listener expect precise alignment of the centre, distribution of the sound event in the
panorama or even spatial depth. This "additional" information will lead to a more authentic musical experience,
the creation of a stage before the listener's eyes without it appearing artificially wide or flat.
Ad 1.
This symmetry is best achieved by placing the speakers in the stereo triangle. The basis width, i.e. the distance
from speaker to speaker, is identical with the distance between speaker and listener. That means:
Distance listener to left speaker = Distance listener to right speaker = Distance left speaker to right speaker.
Thus, the music signal from the right speaker takes the same time to reach the listener's ear as that from the left
speaker. This is important for clear placement.
Our hearing is trained very strongly to perceive the first wave front, i.e. the sound that finds the ear on the direct
path from the source. For this, every tiny offset of this wave front between the left and right place are perceived
and acoustically placed. The sound event is placed where the first wave front is heard first. This is one reason why
a precisely equal distance between the listener's position and the two speakers is all that important. If the spatial
conditions make it impossible to keep the distance between the listener and the two speakers equal, some of our
speakers offer a compensation option: The "Distance Shift". This sets the distance that should be added between
the speaker and the listener to be at the same distance as the other stereo speaker. If the left speaker is 2.6 m
away from the listener, but the right one only 2m, the right one can be returned into symmetry using a "Distance
Shift" of 0.6m.
Ad 2.
Side reflections are essential for stable formation of the virtual stage before the eyes of the listener.
Ideally, no reflection from the side walls should be added to the direct sound. However, this is completely unrealistic,
since most listening rooms have side walls. However, if the room is so large that the side walls and rear wall have
a distance of more than 3 meters, this is referred to as a "free field setup". This simply means that the speakers
are, acoustically speaking, set up in a free field. No side walls will interfere, and playback is not essentially
characterised by the room's character.
While this is generally a desirable situation, such large rooms often have much too long an echo, which distorts
the sound. Symmetry offers a way out of this dilemma again. If the reflection from the left side wall is the same
as on the right, they no longer cause any displacement or tilting of the sound image into one direction.
Therefore, it is important that studio acoustics not only have an equally short echo duration, but also the same
reflexion ratio between the listening monitor and the side wall on the left and right.
Ad 3.
Do not select the listening distance too large. Always adjust it to the speaker's size. A 70cm small speaker heard
at a distance of 5m will cause the listener to hear the room, rather than the speaker.
Strictly speaking, the output behaviour of the speaker plays an important role in the determination of the best
listening distance.
From the horn radiator or our cylindrical wave radiator, a lot more direct sound will reach the listener's ear than
from the traditional round radiator. Therefore, the distance can also be increased a little.
Our speakers with D’ Appolito setup or dedicated waveguide also radiate more directedly than a traditional round
radiator. Therefore, it is important to talk about this aspect with a specialist as well before purchasing a speaker.
KSdigital Referencemonitor